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A toner is comprised of toner particles containing at least a binder resin, a colorant, a wax component and an oxycarboxylic acid. The toner satisfies the following conditions: and wherein A (mg) is a weight of oxycarboxylic acid extracted with methanol from 1 g of the toner, and B (mg) is a weight of oxycarboxylic acid extracted with an aqueous 0.1 mol/liter sodium hydroxide solution from 1 g of the toner.

A magnetic toner for developing an electrostatic latent image has magnetic toner particles containing at least a binder resin, a magnetic powder and a wax component. The magnetic powder has magnetic iron oxide particles the particle surfaces of which have been coat-treated with an organic surface modifying agent. The magnetic iron oxide particles contain silicon element (Si) in an amount of from 0.4 to 2.0% by weight based on the weight of iron element (Fe) and the magnetic iron oxide particles have an Fe/Si atomic ratio of from 1.0 to 4.0 at their outermost surfaces. The magnetic toner particles have shape factors SF-1 and SF-2 as measured by an image analyzer, with a value of SF-1 of from 100 to 160, a value of SF-2 of from 100 to 140 and a value of (SF-2)/(SF-1) of not more than 1.0.

A toner is comprised of a binder resin, a colorant and a wax. The binder resin has a polycarbonate resin in an amount of from 0.1% by weight to 50.0% by weight and a resin other than the polycarbonate resin in an amount of from 50.0% by weight to 99.9% by weight, based on the weight of the binder resin. In molecular weight distribution as measured by gel permeation chromatography of tetrahydrofuran-soluble matter, the toner contains in an amount of 15.0% by weight or less based on the weight of the toner a component which has in its structure a repeating unit of the polycarbonate resin and is contained in components having a molecular weight of 1,000 or less.

A toner for developing electrostatic images is formed from toner particles containing at least a binder resin, a colorant, and a wax. The binder resin comprises a vinyl polymer component and a polyester component. The binder resin contains 40-99 wt. % of a component A, 0-20 wt. % of a component B, and 0-60 wt. % of a component C, the components B and C providing totally 1-60 wt. % of the binder resin. The component A comprises low- and medium-molecular weight components having molecular weights of below 10.sup.6, and the component B comprises high-molecular weight components having molecular weights of at least 106, respectively, based on a chromatogram obtained by gel permeation chromatography of a tetrahydrofuran (THF)-soluble component of the binder resin, and the component C is a THF-insoluble component of the binder resin. The GPC chromatogram of the THF-soluble component of the binder resin exhibits a main peak in a molecular weight region of 3.times.10.sup.3 -5.times.10.sup.4. The toner particles have a shape factor SF-1 of 100-160 and a shape factor SF-2 of 100-140.

A toner for developing an electrostatic image is composed of toner particles containing at least a binder resin, a colorant and a wax composition. The wax composition comprises an ester wax (1) having a long-chain alkyl group, and a wax (2). The wax (2) shows a maximum heat-absorption peak in a range of 40-130.degree. C. on temperature increase on a DSC (differential scanning calorimeter) curve, and gives a .sup.13 C-NMR (nuclear magnetic resonance) spectrum showing a total peak area S in a range of 0-50 ppm, a total peak area S1 in a range of 36-42 ppm, and a total peak area S2 in a range of 10-17 ppm, satisfying: 1.0.ltoreq.(S1/S).times.100.ltoreq.10, 1.5.ltoreq.(S2/S).times.100.ltoreq.15, and S.sub.1

A toner for use in development of electrostatic latent images is disclosed. The toner has toner particles containing a binder resin, a colorant, a wax and a compound of Formula (A): ##STR1## wherein R.sub.1 and R.sub.4 each represent a substituted or unsubstituted aromatic group, inclusive of a condensed ring; R.sub.2 and R.sub.3 each represent a hydrogen atom, an alkyl group, a substituted or unsubstituted aromatic group, inclusive of a condensed ring; M represents an element selected from B, Ti, Fe, Co, Cr, Al and Ni; and X.sup.n+ represents a cation. The toner has the shape factors SF-1 and SF-2 with the specified range. Further, disclosed are a process for producing the toner and an image forming method using the toner.

An electrophotographic toner composition suitable for heat-fixation and showing good storage characteristics is constituted by polymer components, a colorant and a metal-containing organic compound. The toner composition shows a melt index (at 125.degree. C., 10 kg-load) of 5-25 g/10 min., and the polymer components are characterized by (a) containing substantially no THF (tetrahydrofuran)-insoluble content, (b) including a THF-soluble content thereof providing a GPC (gel permeation chromatography) chromatogram showing i) a main peak in a molecular weight region of 2.times.10.sup.3 -3.times.10.sup.4, and a sub-peak or shoulder in a molecular weight region of at least 10.sup.5, and ii) an areal percentage of 3-10% in a molecular weight region of at least 10.sup.6, and (c) including a polymer component (H) in a molecular weight region of at least 10.sup.5 obtained by polymerization using a polyfunctional polymerization initiator and a monofunctional polymerization initiator.

A toner for developing electrostatic images includes a binder resin, a specific long-chain alkyl compound and a specific azo iron complex. The long-chain alkyl compound contains a terminal --OH or --COOH group and from about 35 to 150 (--CH.sub.2 --) groups. The azo iron complex has a cation including 75-98 mol. % of ammonium ion and another ion which is hydrogen, sodium, potassium or mixtures thereof.

A magnetic developer for developing electrostatic images is constituted by magnetic toner particles, each containing a binder resin having a melt viscosity of at most 5.0.times.10.sup.6 poise at 150.degree. C. and a magnetic material. The magnetic material is blended with a proportion (C) [wt. %] of inorganic fine particles based on the magnetic material to carry 0.2-5 wt. % of the inorganic fine particles secured to the magnetic material surface. The magnetic material has a specific surface area (A) [m.sup.2 /g] before securing of the inorganic fine particles and is provided with an increase in surface area (B) [m.sup.2 /g] by the securing of the inorganic fine particles; wherein the parameters A, B and C satisfy the following formulae (1) and (2): As a result, the magnetic developer is provided with an improved low-temperature fixability without causing problems accompanying the use of a low-temperature softening binder resin, such as deterioration of anti-offset characteristic, storage characteristic, developing characteristic.